Control of cellular processes, biodegradation and mechanical properties of biomaterial scaffolds is critical in the development of tissue engineering devices. It is widely recognized that scaffold architecture, in particular, can profoundly influence the success of the construct. The advancement of bone tissue engineering strategies is strongly dependent on the development of high-porosity scaffolds that can withstand rigorous in vivo loading. The proposed research utilizes emulsion templating to generate novel microcellular polymers as injectable, biodegradable scaffolds for bone regeneration. Emulsion templating is a relatively new method for the production of highly porous scaffolds and involves the template polymerization of high internal phase emulsions (HIPEs). The control of scaffold architecture afforded by emulsion templating makes polyHIPE materials attractive candidates for tissue engineering scaffolds. In addition, HIPEs can be made without solvent, have an emulsion viscosity that permits injectability, and cure at or around body temperature. We propose to tune the emulsion assembly processes to generate polyHIPE architectures with improved mechanical properties and target degradation profiles. We hypothesize that the high porosity and interconnectivity of these scaffolds will augment tissue regeneration by facilitating cellular in-growth, the influx of nutrients and the transport of waste throughout the scaffold. The Specific Aims are: 1) Develop and characterize a library of injectable polyHIPE scaffolds with interconnected porosity. 2) Evaluate polyHIPE scaffolds developed in Aim 1 as osteoconductive tissue engineering scaffolds. Successful completion of these Aims will generate high porosity scaffolds that are both biodegradable and injectable. A highly porous scaffold that is injectable and cures in situ to suitable mechanical strength represents a significant advancement in orthopaedic tissue engineering. This innovative fabrication design also provides exceptional control over the architecture which can be utilized to probe key relationships in tissue regeneration. Although these studies are focused on bone repair, emulsion templating can be utilized to generate a wide variety of functional grafts. PUBLIC HEALTH RELEVANCE: Nationwide Inpatient Statistics show that over 1.1 million surgical procedures involving the partial excision of bone, bone grafting, and inpatient fracture repair were performed in 2004 alone, with an estimated total cost of over $5 billion. Engineered tissue grafts have the potential to repair damaged tissues when traditional transplants are unavailable or fail. The proposed research utilizes emulsion templating to generate injectable, biodegradable scaffolds for the repair of bone defects.